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The quiescent bradyzoites or cystizoites that occupy cysts in infected tissue.Although tissue cysts are less resistant to environmental conditions than oocysts, they are relatively resistant to changes in temperature and remain infectious in refrigerated carcasses (1- 4 ?C) or minced meat for up to 3 weeks, i.e. probably as long as the meat remains suitable for human consumption (Saavedra, 2003). Although most tissue cysts are killed at temperatures of -12?C or lower, occasionally some tissue cysts may survive in deep freeze, and it has even been suggested that some strains of Toxoplasma may be resistant to freezing (Dubey, 2002).It is used to describe the bradyzoites organism multiplying slowly within a tissue cyst (Fig.The parasite remains viable within cysts as long as the immune system is intact, but if diminished, the cyst wall will open and active tachyzoites will start to invade other cells and multiply (Gazzinelli et al., 1996).The spheroidal cyst, had very resistance membrane contain as few as 50 and up to as several thousand (bradyzoites) which has only come into contact with host cells, if the cyst exposure to the stress will give ruptures (Lambert, 2009).Tissue cysts are formed most commonly in the brain, liver and muscles (Hakan et al., 2010).Its morphology is similar to that of tachyzoite except the former contains higher amount of polysaccharide and it can give rise positive reaction with periodic acid shift (PAS) (Markell, 1999).They are more slender than tachyzoites and their nucleus located more to the posterior end (Jones and Dubey, 2010). 1).

The quiescent bradyzoites or cystizoites that occupy cysts in infected tissue.
Bradyzoite observed during the chronic stage of disease (Tobin et al., 2010). The
spheroidal cyst, had very resistance membrane contain as few as 50 and up to as
several thousand (bradyzoites) which has only come into contact with host cells, if
the cyst exposure to the stress will give ruptures (Lambert, 2009). Tissue cysts are
formed most commonly in the brain, liver and muscles (Hakan et al., 2010). The
parasite remains viable within cysts as long as the immune system is intact, but if
diminished, the cyst wall will open and active tachyzoites will start to invade other
cells and multiply (Gazzinelli et al., 1996).
Its morphology is similar to that of tachyzoite except the former contains higher
amount of polysaccharide and it can give rise positive reaction with periodic acid
shift (PAS) (Markell, 1999).
They are more slender than tachyzoites and their nucleus located more to the
posterior end (Jones and Dubey, 2010). The term ''bradyzoite'' brady= (slow in
Greek) was also coined by Frenkel (1973). It is used to describe the bradyzoites
organism multiplying slowly within a tissue cyst (Fig. 1).
Although tissue cysts are less resistant to environmental conditions than
oocysts, they are relatively resistant to changes in temperature and remain
infectious in refrigerated carcasses (1- 4 °C) or minced meat for up to 3 weeks, i.e.
probably as long as the meat remains suitable for human consumption (Saavedra,
2003). Although most tissue cysts are killed at temperatures of -12°C or lower,
occasionally some tissue cysts may survive in deep freeze, and it has even been
suggested that some strains of Toxoplasma may be resistant to freezing (Dubey,
2002).